1. Field of the Invention
The present invention relates to a portable telephone, and, in particular, to a portable telephone which is provided with a multi-function key-switch unit which is operated in a manner in which a key top is inclined in a plurality of directions.
In the future, a portable telephone will have a computer function by having a browser built therein, in addition to an original radio communication function. When having a computer function, a portable telephone is provided with a multi-function key-switch unit or the like which is operated as an operator operates a personal computer. Because a portable telephone is smaller than a general personal computer, it is necessary to design a special contrivance.
2. Description of the Related Art
FIG. 1A shows a multi-function key-switch unit 10 which is incorporated in a portable telephone in the related art. A key top 11 of the multi-function key-switch unit 10 in the related art is placed on a telephone-body assembly 12, and is contained in an opening 14 of a portable-telephone case 13. Pushing projections 16 are formed at four positions on the periphery on the bottom surface of the key top 11. The telephone body 12 has a printed-circuit board 17 on the top surface thereof. A plurality of dome switches 18-1 and 18-2 (actually, four dome switches) are provided on the printed-circuit board 17 at positions at which the key top 11 is placed. Each of the dome switches 18-1 and 18-2 includes a fixed contact formed on the printed-circuit board 17 and a dome-shaped movable contact member 19 which covers the fixed contact.
For example, when the key top 11 is operated in a manner in which a position 20 on the top surface 11a of the key top 11 is pushed, the key top 11 inclines as shown in FIG. 1B. As a result, the pushing projection 16 pushes the movable contact member 19 so that the dome switch 18-1 is turned on.
In the multi-function key-switch unit 10 in the related art, the plurality of dome switches 18-1 and 18-2 (actually, the four dome switches) are disposed, and the dome-shaped movable contact member 19 is provided in each dome switch, as mentioned above. Therefore, it is difficult to miniaturize the multi-function key-switch unit 10. Accordingly, the multi-function key-switch unit 10 in the related art is not suitable for being incorporated in a portable telephone which is small.
An object of the present invention is to provide a portable telephone in which the above-mentioned problem is solved.
A portable telephone according to the present invention comprises a multi-function key-switch unit in which a key top is operated in a plurality of directions. The multi-function key-switch unit comprises a stick switch which comprises a switch body and a stick projecting from the switch body, and the approximately cylindrical key top which is attached to the stick. The key top has a stopper portion provided on the bottom surface thereof, the stopper portion coming into contact with the switch body when the key top is operated to more than a predetermined degree so as to prevent the key top from inclining more than a predetermined angle.
In this arrangement, because the stopper portion is provided, when an operation is performed with a strong force, the stick switch can be protected. Further, because the stopper portion is provided on the bottom surface of the key top, it is possible to provide a mechanism, for preventing the key top from being inclined more than the predetermined angle, without increasing the size of the multi-function key-switch unit in the plan view thereof. Further, because what the stopper comes into contact with is the switch body, the multi-function key-switch unit itself can form the mechanism for preventing the key top from being inclined more than the predetermined angle. As a result, the maximum inclination angle of the key top is not affected by the variation in the accuracy with which the multi-function key-switch unit is incorporated into the portable telephone.
A portable telephone according to another aspect of the present invention comprises a multi-function key-switch unit in which a key top is operated in a plurality of directions. The multi-function key-switch unit comprises a stick switch which comprises a switch body and a stick projecting from the switch body, and the approximately cylindrical key top which is attached to the stick. The key top has a key-top body and a shaft projecting from a center of a bottom surface of the key-top body, the shaft having a nail portion which projects from an outer circumferential surface of the shaft. The stick has a pipe shape and an engagement opening in a circumference wall thereof, the nail portion engaging with the engagement opening. The stick further has a slit which extends from the engagement opening to a top end of the stick, the slit causing the pipe-shaped stick to be easily increased in a diameter thereof. The shaft of the key top is fitted into the pipe-shaped stick and the nail portion engages with the engagement opening.
In this arrangement, when a moment is developed in the key top and force of causing the shaft to slip off from the stick is developed, because the slit is provided, the pipe-shaped stick can be easily increased in the diameter thereof, and, thereby, the nail portion can easily slip out from the engagement opening. As a result, the stick switch can be protected.
A portable telephone according to another aspect of the present invention comprises a multi-function key-switch unit in which a key top is operated in a plurality of directions. The multi-function key-switch unit comprises a stick switch which comprises a switch body and a stick projecting from the switch body, and the approximately cylindrical key top which is attached to the stick. The key top has a key-top body and a shaft projecting from a center of a bottom surface of the key-top body, the shaft having a nail portion which projects from an outer circumferential surface of the shaft and a slit on a bottom-end side thereof, the slit causing the shaft to be easily reduced in a diameter thereof. The stick has a pipe shape and an engagement opening in a circumferential wall thereof, the nail portion engaging with the engagement opening. The shaft of the key top is fitted into the pipe-shaped stick and the nail portion engages with the engagement opening.
In this arrangement, because the slit is provided, the slit is narrowed and the shaft is easily reduced in the diameter thereof. As a result, the nail portion easily retreats from the engagement opening. Thereby, when the moment is developed in the key top and the force of causing the shaft to slip off from the stick is developed, the nail portion can easily slip out from the engagement opening. As a result, the stick switch can be protected.
A portable telephone according to another aspect of the present invention comprises a multi-function key-switch unit in which a key top is operated in a plurality of directions, the key top being exposed from an opening of a case of the portable telephone. The multi-function key-switch unit comprises a stick switch which comprises a switch body and a stick projecting from the switch body, and the approximately cylindrical key top which is attached to the stick. The key top has a plurality of recess portions at a periphery thereof. The case has projections on an edge of the opening. The recess portions of the key top are fitted to the projections of the case so that the key top is prevented from rotating about an axis line thereof.
A portable telephone according to another aspect of the present invention comprises a multi-function key-switch unit in which a key top is operated in a plurality of directions, the key top being exposed from an opening of a case of the portable telephone. The multi-function key-switch unit comprises a stick switch which comprises a switch body and a stick projecting from the switch body, and the approximately cylindrical key top which is attached to the stick. The key top has a plurality of projections at a periphery thereof. The case has recess portions on an edge of the opening. The projections of the key top are fitted to the recess portions of the case so that the key top is prevented from rotating about an axis line thereof.
In each of these arrangements, because the key top is prevented from rotating about the axis line thereof, when an operator operates the key top so as to rotate the key top with malicious intent, the stick switch can be prevented from being damaged.
A portable telephone according to another aspect of the present invention comprises a multi-function key-switch unit in which a key top is operated in a plurality of directions, the key top being exposed from an opening of a case of the portable telephone. The key top has a flexible ring-shaped membrane member which extends outward. The ring-shaped membrane member is in contact with an edge of the opening of the case.
In this arrangement, because the flexible ring-shaped membrane member is in contact with the edge of the opening of the case, the gap between the key top and the opening of the case is covered by this membrane member. As a result, dust can be prevented from passing through the gap and entering the portable telephone. Thus, it is possible to achieve the portable telephone in which a dust-proof function is provided.
A portable telephone according to another aspect of the present invention comprises a multi-function key-switch unit in which a key top is operated in a plurality of directions, the key top being exposed from an opening of a case of the portable telephone, the portable telephone further comprising a keypad-collection member having the property of rubber. The key top has an elastically compressible ring member attached to a circumferential surface thereof. The keypad-collection member has a ring-shaped wall at a portion thereof, the ring-shaped wall surrounding the key top. The ring member is in contact with an inner circumferential surface of the ring-shaped wall.
In this arrangement, because the ring member is in contact with the inner circumferential surface of the ring-shaped wall, the gap between the key top and the opening of the case is covered by this ring member. As a result, dust can be prevented from passing through the gap and entering the portable telephone. Because the ring member is elastically compressible, an operation of inclining the key top can be performed without difficulty.
A portable telephone according to another aspect of the present invention comprises a multi-function key-switch unit in which a key top is operated in a plurality of directions, the key top being exposed from an opening of a case of the portable telephone. A packing member is provided, the packing member having a size such that the packing member can surround the multi-function key-switch unit, the packing member being mounted on a printed-circuit board on which the multi-function key-switch unit is mounted, the packing member surrounding the multi-function key-switch unit, and the packing member being sandwiched between the printed-circuit board and a shielding member which covers the printed-circuit board. The packing member covers an opening formed between a periphery of the multi-function key-switch unit and an inner edge of an opening window which is formed in the shielding member, the opening window being larger than the multi-function key-switch unit.
In this arrangement, because the packing member covers the opening formed between the periphery of the multi-function key-switch unit and the inner edge of the opening window which is formed in the shielding member, dust can be prevented from entering a space on the printed-circuit board without attaching a special sealing member to the key top.
A portable telephone according to another aspect of the present invention comprises a multi-function key-switch unit. The multi-function key-switch unit comprises a knob which is exposed from an opening of a case of the portable telephone, the knob being movable approximately straightly in opposite directions about a central position, the knob being pushable at the central position, a spring-type contact member which is attached to the knob, the spring-type contact member moving integrally with the knob and sliding on a contact pattern, and a dome-shaped movable contact member which is deformed by the knob.
In this arrangement, because the knob is operated so as to be moved straightly, it is possible that the stroke of the knob is relatively long. As a result, an erroneous operation in which a switch which is not desired to be turned on is turned on is hardly performed.
A portable telephone according to another aspect of the present invention is provided with an infrared module into which an infrared-emitting element and an infrared-receiving element are incorporated, shielding treatment being performed on the infrared module.
In this arrangement, the portable telephone has a data communication function using infrared rays. Therefore, when mobile computing is performed, it is not necessary to use a cable for connecting the portable telephone to a portable personal computer. It is sufficient that the infrared module of the portable telephone is caused to face an infrared module of the portable personal computer. Thereby, work of connecting of a cable is not needed. As a result, it is possible to achieve the portable telephone which can be easily used. Further, because the infrared module has the shielding treatment performed thereon, an electromagnetic wave mainly emitted from the infrared-emitting element is shielded in the infrared module, and electronic parts which are located outside of the infrared module can be prevented from being affected by the electromagnetic wave. Therefore, the communication function which is the original function of the portable telephone is not adversely affected.
A portable telephone according to another aspect of the present invention is provided with an infrared module into which an infrared-emitting element and an infrared-receiving element are incorporated, the infrared module having a visible-light-emitting element which emits visible light when communication is performed using infrared rays. A window panel in front of the infrared module has an arrangement in which visible light is transmitted through the window panel at a portion at which the visible-light-emitting element emits visible light.
In this arrangement, by visually confirming that the predetermined portion of the window panel is bright, it is possible to confirm that the infrared module of the portable telephone is communicating with an infrared module of a portable personal computer using infrared rays. As a result, it is possible to confirm that the infrared module of the portable telephone is communicating with the infrared module of the portable personal computer using infrared rays while performing mobile computing. Thus, it is possible to perform mobile computing positively without anxiety.
A portable telephone according to another aspect of the present invention has a composite infrared module in which an infrared module into which an infrared-emitting element and an infrared-receiving element are incorporated and a terminal module in which one of a battery terminal and a signal terminal is incorporated in a block made of synthetic resin are integrated. The composite infrared module is positioned so that the one of the battery terminal and the signal terminal comes into contact with a terminal of a battery which is loaded in the portable telephone.
In this arrangement, the composite infrared module is mounted by effectively using a space in which a connector is provided in the related art. The connector is provided in the portable telephone in the related art, but is not provided in the portable telephone according to the present invention because the infrared module is provided so that the connector is not needed. Therefore, the composite infrared module can be incorporated into the portable telephone without specially enlarging the size thereof.
Other objects and further features of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.